Comprehensive Laboratory Evaluation for Dysphagia
For a patient with dysphagia, a complete laboratory workup should include imaging studies such as videofluoroscopy or modified barium swallow as the primary diagnostic test, along with additional laboratory tests to evaluate the entire differential diagnosis.
Initial Diagnostic Approach
Videofluoroscopy/Modified Barium Swallow: This is the preferred initial imaging study for dysphagia evaluation, as it can assess both oral and pharyngeal phases of swallowing, including bolus manipulation, tongue motion, pharyngeal elevation, and laryngeal penetration 1
Biphasic Esophagram: Should be performed to evaluate the entire esophagus and gastric cardia, as abnormalities in these areas can cause referred dysphagia to the pharynx 1
Complete Blood Count (CBC): To assess for signs of infection, inflammation, or anemia that may be associated with various causes of dysphagia 2
Neurological Causes Assessment
ALS Functional Rating Scale-Revised (ALSFRS-R) or ALS Swallowing Severity Scale (ALSSS): For patients with suspected neurological causes of dysphagia 1
Structured questionnaires: Such as EAT-10 (Eating Assessment Tool), which has high sensitivity (86%) and specificity (76%) for identifying aspiration risk in patients with neurological disorders 1
Volume-Viscosity Swallowing Test (V-VST): Clinical screening test with 92% sensitivity and 80% specificity for detecting dysphagia in neurological patients 1
Infectious Causes Evaluation
HIV testing: Consider in all patients with unexplained dysphagia, as HIV-related opportunistic infections are common causes of esophageal symptoms 3, 4
CD4 count: For HIV-positive patients, as lower CD4 counts (particularly <50 cells/mm³) correlate strongly with esophageal symptoms 5
Esophageal brushings and biopsies: To evaluate for Candida albicans (most common pathogen), cytomegalovirus (CMV), herpes simplex virus (HSV), and other opportunistic infections in immunocompromised patients 3, 5
Inflammatory and Structural Causes
Esophageal manometry: To evaluate for motility disorders that may contribute to dysphagia, particularly in patients with persistent symptoms despite treatment of identified causes 3
Endoscopic evaluation: For direct visualization of the esophagus and to obtain tissue samples for histopathology 4, 6
Eosinophil count in esophageal biopsies: To diagnose eosinophilic esophagitis, an increasingly recognized cause of dysphagia that can occur even in immunocompromised patients 6
Additional Testing Based on Clinical Suspicion
Scintigraphy: May be useful to assess esophageal transit and evaluate for motility abnormalities or gastroesophageal reflux 1
Computed Tomography (CT) angiography: Consider in hemodynamically stable patients with suspected vascular causes of dysphagia 1
Fiberoptic Endoscopic Evaluation of Swallowing (FEES): Alternative to videofluoroscopy for direct visualization of the swallowing mechanism 1
Nutritional Status Assessment
Body Mass Index (BMI): To evaluate for malnutrition, which is present in 0-21% of patients with dysphagia at diagnosis and 7.5-53% during follow-up 1
Weight loss assessment: Weight loss >10% is indicative of malnutrition in 21-48% of patients with dysphagia 1
Albumin levels: To assess nutritional status, particularly in patients being considered for enteral feeding 1
Important Clinical Considerations
Dysphagia can be a symptom of both oropharyngeal and esophageal disorders, so a comprehensive evaluation of both regions is essential 1
Abnormalities in the mid or distal esophagus can cause referred dysphagia to the pharynx, so the entire esophagus should be evaluated even in patients with apparent oropharyngeal symptoms 1
In patients with neurological disorders, dysphagia may be present even in the absence of symptoms, so objective testing is crucial 1
For patients with persistent symptoms despite treatment, consider repeat testing to evaluate for persistent or new pathology 3